Export (0) Print
Expand All

Int64.Parse Method (String, IFormatProvider)

Converts the string representation of a number in a specified culture-specific format to its 64-bit signed integer equivalent.

Namespace:  System
Assembly:  mscorlib (in mscorlib.dll)

Public Shared Function Parse ( _
	s As String, _
	provider As IFormatProvider _
) As Long


Type: System.String

A string containing a number to convert.

Type: System.IFormatProvider

An object that supplies culture-specific formatting information about s.

Return Value

Type: System.Int64
A 64-bit signed integer equivalent to the number specified in s.


s is Nothing.


s is not in the correct format.


s represents a number less than MinValue or greater than MaxValue.

This overload of the Parse(String, IFormatProvider) method is typically used to convert text that can be formatted in a variety of ways to an Int64 value. For example, it can be used to convert the text entered by a user into an HTML text box to a numeric value.

The s parameter contains a number of the form:


Items in square brackets ([ and ]) are optional, and other items are as follows.


An optional white space.


An optional sign.


A sequence of digits ranging from 0 to 9.

The s parameter is interpreted using the NumberStyles.Integer style. In addition to decimal digits, only leading and trailing spaces together with a leading sign are allowed. To explicitly define the style elements that can be present in s, use the Int64.Parse(String, NumberStyles, IFormatProvider) method.

The provider parameter is an IFormatProvider implementation, such as a NumberFormatInfo or CultureInfo object. The provider parameter supplies culture-specific information about the format of s. If provider is Nothing, the NumberFormatInfo for the current culture is used.

The following example is the button click event handler of a Web form. It uses the array returned by the HttpRequest.UserLanguages property to determine the user's locale. It then instantiates a CultureInfo object that corresponds to that locale. The NumberFormatInfo object that belongs to that CultureInfo object is then passed to the Parse(String, IFormatProvider) method to convert the user's input to an Int64 value.

Protected Sub OkToLong_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles OkToLong.Click
   Dim locale As String 
   Dim culture As CultureInfo
   Dim number As Long 

   ' Return if string is empty 
   If String.IsNullOrEmpty(Me.inputNumber.Text) Then Exit Sub 

   ' Get locale of web request to determine possible format of number 
   If Request.UserLanguages.Length = 0 Then Exit Sub
   locale = Request.UserLanguages(0)
   If String.IsNullOrEmpty(locale) Then Exit Sub 

   ' Instantiate CultureInfo object for the user's locale
   culture = New CultureInfo(locale)

   ' Convert user input from a string to a number 
      number = Int64.Parse(Me.inputNumber.Text, culture.NumberFormat)
   Catch ex As FormatException
      Exit Sub 
   Catch ex As Exception
      Exit Sub 
   End Try 

   ' Output number to label on web form 
   Me.outputNumber.Text = "Number is " & number.ToString()
End Sub

.NET Framework

Supported in: 4.6, 4.5, 4, 3.5, 3.0, 2.0, 1.1

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Portable Class Library

Supported in: Portable Class Library

Supported in: Windows Phone 8.1

Supported in: Windows Phone Silverlight 8.1

Supported in: Windows Phone Silverlight 8
© 2015 Microsoft